<template>
  <div class="app-container">
    <!--表单-->
    <el-form :inline="true" class="demo-form-inline">

      <el-form-item>
        <el-select v-model="searchObj.type" clearable placeholder="请选择">
          <el-option label="学员登录数统计" value="login_num"/>
          <el-option label="学员注册数统计" value="register_num"/>
          <el-option label="课程播放数统计" value="video_view_num"/>
          <el-option label="每日课程数统计" value="course_num"/>
        </el-select>
      </el-form-item>

      <el-form-item>
        <el-date-picker
          v-model="searchObj.begin"
          type="date"
          placeholder="选择开始日期"
          value-format="yyyy-MM-dd"/>
      </el-form-item>
      <el-form-item>
        <el-date-picker
          v-model="searchObj.end"
          type="date"
          placeholder="选择截止日期"
          value-format="yyyy-MM-dd"/>
      </el-form-item>
      <el-button
        :disabled="btnDisabled"
        type="primary"
        icon="el-icon-search"
        @click="showChart()">查询
      </el-button>
    </el-form>

    <div class="chart-container">
      <div id="chart" class="chart" style="height:500px;width:100%"/>
    </div>
  </div>
</template>

<script>
  import echarts from 'echarts'
  import daily from '@/api/statistics/sta'

  export default {
    data() {
      return {
        searchObj: {
          type: 'login_num',
          begin: '',
          end: ''
        },
        btnDisabled: false,
        chart: null,
        title: '',
        xData: [],
        yData: []
      }
    },created() {
      //生成默认日期
      this.addDate()

    },
    methods: {
      showChart() {
        this.initChartData()
        this.setChart()

      },

      // 准备图表数据
      initChartData() {
        daily.showChart(this.searchObj).then(response => {
          // 数据
          this.yData = response.data.dataList

          // 横轴时间
          this.xData = response.data.dateList

          // 当前统计类别
          switch (this.searchObj.type) {
            case 'register_num':
              this.title = '学员注册数统计'
              break
            case 'login_num':
              this.title = '学员登录数统计'
              break
            case 'video_view_num':
              this.title = '课程播放数统计'
              break
            case 'course_num':
              this.title = '每日课程数统计'
              break
          }

          this.setChart()
        })
      },
      //获取当前年月日
      addDate(){
        const nowDate = new Date();
        const date = {
          year: nowDate.getFullYear(),
          month: nowDate.getMonth() + 1,
          date: nowDate.getDate(),
        }
        const newmonth = date.month>10?date.month:'0'+date.month
        const day = date.date>10?date.date:'0'+date.date
        this.searchObj.end = date.year + '-' + newmonth + '-' + day
        this.searchObj.begin =this.getBeforeDate(7, this.searchObj.end)
      },
      //生成指定日期的前n天日期
      getBeforeDate(num, time) {
        let n = num;
        let d = '';
        if(time) {
          d = new Date(time);
        } else {
          d = new Date();
        }
        let year = d.getFullYear();
        let mon = d.getMonth() + 1;
        let day = d.getDate();
        if(day <= n) {
          if(mon > 1) {
            mon = mon - 1;
          } else {
            year = year - 1;
            mon = 12;
          }
        }
        d.setDate(d.getDate() - n);
        year = d.getFullYear();
        mon = d.getMonth() + 1;
        day = d.getDate();
        let s = year + "-" + (mon < 10 ? ('0' + mon) : mon) + "-" + (day < 10 ? ('0' + day) : day);
        return s;
      },
      // 设置图标参数
      setChart() {
        // 基于准备好的dom，初始化echarts实例
        this.chart = echarts.init(document.getElementById('chart'))
        // console.log(this.chart)

        // 指定图表的配置项和数据
        var option = {
          // x轴是类目轴（离散数据）,必须通过data设置类目数据
          xAxis: {
            type: 'category',
            data: this.xData//-------绑定数据
          },
          // y轴是数据轴（连续数据）
          yAxis: {
            type: 'value'
          },
          // 系列列表。每个系列通过 type 决定自己的图表类型
          series: [{
            // 系列中的数据内容数组
            data: this.yData,//-------绑定数据
            // 折线图
            type: 'line'
          }],
          //显示标题
          title: {
            text: this.title
          },
          //x坐标轴触发提示
          tooltip: {
            trigger: 'axis'
          },
          //区域缩放
          /*dataZoom: [{
            show: true,
            height: 30,
            xAxisIndex: [
              0
            ],
            bottom: 30,
            start: 10,
            end: 80,
            handleIcon: 'path://M306.1,413c0,2.2-1.8,4-4,4h-59.8c-2.2,0-4-1.8-4-4V200.8c0-2.2,1.8-4,4-4h59.8c2.2,0,4,1.8,4,4V413z',
            handleSize: '110%',
            handleStyle: {
              color: '#d3dee5'

            },
            textStyle: {
              color: '#fff'
            },
            borderColor: '#90979c'
          },
            {
              type: 'inside',
              show: true,
              height: 15,
              start: 1,
              end: 35
            }]*/
        }

        this.chart.setOption(option)
      }
    }
  }
</script>

<style scoped>

</style>
